Unity
Keystone Utilities — 10 Systems: State Machine, Event Bus, Save System & More
By ccodeccraft
$29.99
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About Keystone Utilities — 10 Systems: State Machine, Event Bus, Save System & More
- Tools, Systems & Learning > Game Templates & Systems
480+ automated tests. Zero forced dependencies. Ten systems, take them one at a time.
Keystone Utilities is a toolkit of ten independent, production-ready systems covering the gameplay-programming groundwork almost every Unity project needs:
Event Bus — Systems communicate through typed events, not direct references — priority ordering, filters, one-shot subscriptions, deferred dispatch, interceptors, and event history for debugging.
Command Pattern — Execute/Undo/Redo, built in from the start — composite macros, sequential queues, cooldowns, and middleware, the backbone of RTS controls, editors, and replay systems.
State Machine — Pause without losing gameplay state — push a state on top, pop it to resume exactly where you left off, with guarded transitions and automatic input/music context switching.
Object Pooling — Prewarmed, reusable instances — no runtime Instantiate/Destroy, hard caps, auto-expand, auto-return, zero allocation in your hot path.
Coroutine Timer — Delay, repeat, and countdown timers that run from any plain C# class — no MonoBehaviour required.
Audio Manager — Centralized playback for every sound in the game — pooled SFX, cross-fading music, auto-persisted per-channel volume/mute, 3D and following sounds.
Input Manager — Named actions with contexts — live rebinding, mobile virtual axes, swipe detection, and a swappable backend for testing or new input systems.
Save System — Multi-slot saves, production-ready from the start — version migration, autosave, a save-select-ready manifest API, JSON or lightweight-obfuscated binary.
Singleton — The MonoBehaviour singleton base class — done once, correctly, with quit-safety and duplicate protection.
Metadata Loader — One API for loading JSON, CSV, and XML from Resources, StreamingAssets, or disk — including the Android-safe async path everyone forgets.
Take only what you need. Most systems have zero dependency on anything else in the package — drop any one into a project alone. Exact per-system details are in the manual.
Every public method is covered in the included manual. Every system gets its own interactive demo scene — real buttons, live stats panels, no console-log spelunking required — plus a companion *_Examples.cs file behind it demonstrating every feature in code. A combined "Arena Survival" scene shows all ten systems working together in one small playable 3-wave combat loop.
Each system is a complete, production-ready tool on its own — not a stripped-down piece that only makes sense bundled with the rest. Use several together, though, and nothing feels bolted on: same Event Bus, same test suite, same conventions throughout, built and tested as one set rather than glued together after the fact. Whether you're prototyping a game jam entry or laying the foundation for a full production, the plumbing here is already done — alone or combined.
What's included
Full C# source for all 10 systems (Assets/GameKit/Scripts), compiled into its own assembly
A Hub scene plus an interactive demo scene per system, and a combined "Arena Survival" scene (Assets/GameKit/Demo)
A full example script per system demonstrating every feature
README.md quick-start guide, MANUAL.md full reference, and CHANGELOG.md version history
Keystone Utilities is a toolkit of ten independent, production-ready systems covering the gameplay-programming groundwork almost every Unity project needs:
Event Bus — Systems communicate through typed events, not direct references — priority ordering, filters, one-shot subscriptions, deferred dispatch, interceptors, and event history for debugging.
Command Pattern — Execute/Undo/Redo, built in from the start — composite macros, sequential queues, cooldowns, and middleware, the backbone of RTS controls, editors, and replay systems.
State Machine — Pause without losing gameplay state — push a state on top, pop it to resume exactly where you left off, with guarded transitions and automatic input/music context switching.
Object Pooling — Prewarmed, reusable instances — no runtime Instantiate/Destroy, hard caps, auto-expand, auto-return, zero allocation in your hot path.
Coroutine Timer — Delay, repeat, and countdown timers that run from any plain C# class — no MonoBehaviour required.
Audio Manager — Centralized playback for every sound in the game — pooled SFX, cross-fading music, auto-persisted per-channel volume/mute, 3D and following sounds.
Input Manager — Named actions with contexts — live rebinding, mobile virtual axes, swipe detection, and a swappable backend for testing or new input systems.
Save System — Multi-slot saves, production-ready from the start — version migration, autosave, a save-select-ready manifest API, JSON or lightweight-obfuscated binary.
Singleton — The MonoBehaviour singleton base class — done once, correctly, with quit-safety and duplicate protection.
Metadata Loader — One API for loading JSON, CSV, and XML from Resources, StreamingAssets, or disk — including the Android-safe async path everyone forgets.
Take only what you need. Most systems have zero dependency on anything else in the package — drop any one into a project alone. Exact per-system details are in the manual.
Every public method is covered in the included manual. Every system gets its own interactive demo scene — real buttons, live stats panels, no console-log spelunking required — plus a companion *_Examples.cs file behind it demonstrating every feature in code. A combined "Arena Survival" scene shows all ten systems working together in one small playable 3-wave combat loop.
Each system is a complete, production-ready tool on its own — not a stripped-down piece that only makes sense bundled with the rest. Use several together, though, and nothing feels bolted on: same Event Bus, same test suite, same conventions throughout, built and tested as one set rather than glued together after the fact. Whether you're prototyping a game jam entry or laying the foundation for a full production, the plumbing here is already done — alone or combined.
What's included
Full C# source for all 10 systems (Assets/GameKit/Scripts), compiled into its own assembly
A Hub scene plus an interactive demo scene per system, and a combined "Arena Survival" scene (Assets/GameKit/Demo)
A full example script per system demonstrating every feature
README.md quick-start guide, MANUAL.md full reference, and CHANGELOG.md version history